ABSTRACT
Multiple morphological abnormalities of the sperm flagella (MMAF) is a severe form of asthenozoospermia categorized by immotile spermatozoa with abnormal flagella in ejaculate. Whole-exome sequencing (WES) is used to detect pathogenic variants in patients with MMAF. In this study, a novel homozygous frameshift variant (c.6158_6159insT) in dynein axonemal heavy chain 8 (DNAH8) from two infertile brothers with MMAF in a consanguineous Pakistani family was identified by WES. Reverse transcription-polymerase chain reaction (RT-PCR) confirmed DNAH8 mRNA decay in these patients with the DNAH8 mutation. Hematoxylin-eosin staining and transmission electron microscopy revealed highly divergent morphology and ultrastructure of sperm flagella in these patients. Furthermore, an immunofluorescence assay showed the absence of DNAH8 and a reduction in its associated protein DNAH17 in the patients' spermatozoa. Collectively, our study expands the phenotypic spectrum of patients with DNAH8-related MMAF worldwide.
Subject(s)
Humans , Male , Consanguinity , Pakistan , Infertility, Male/metabolism , Semen/metabolism , Sperm Tail/metabolism , Spermatozoa/metabolism , Flagella/pathology , MutationABSTRACT
An unusual morphological type of Trypanosoma (Herpetosoma) lewisi (Kent, 1880) which was detected in Rattus norvegicus in India is reported in the present study. This type is different from known types of T. lewisi in that the kinetoplast is at a greater distance from the posterior end (P-K) than the usual type. The total length, including the free flagellum, is 35.3-39.3 microns and P-K is 11.9-15.0 as against total length of 21 to 36.5 microns in the normal form.